"Given the chaotic and totally unpredictable situation in the city, getting from one place to another involves incalculable risks," spokesman Florian Westphal said.
The Red Cross said one of its staff is missing in Baghdad and is feared to have been seriously injured when the vehicle he was traveling in was hit by gunfire.
Vatche Arslanian, 48, a Canadian who is in charge of logistics for the International Committee of the Red Cross in Iraq, has not been seen since Tuesday afternoon, the agency said.
Two other ICRC staff members who were with Arslanian when their vehicle was hit escaped and were able to reach the agency's offices and raise the alarm. The group has six international employees in Baghdad along with local staff.
"The ICRC has so far been unable to approach the area where its staff member was last seen. Delegates who tried to rescue him had to turn back because of the ongoing fighting," the ICRC said in a statement. "There is at present no news of his whereabouts or condition."
It said it was impossible to establish whether the vehicle was caught in crossfire or came under direct attack.
"The two vehicles were clearly marked with large red crosses visible from a distance," the ICRC said.
One of the main tasks of the Red Cross is to distribute to hospitals special kits for treating war wounded. Baghdad hospitals are running out of supplies to treat war casualties, the World Health Organization (WHO) said Tuesday.
"There's a shortage of equipment to deal with burns, shrapnel wounds and spinal injuries," WHO spokesman Iain Simpson told reporters.
WHO has a convoy of medical equipment on standby in neighboring Jordan, but it has been unable to leave for Baghdad because of the battle for the capital, Simpson said.
"Before the war started there were enough supplies for a normal medical situation," he said. "This is not a normal situation."
WHO officials have no estimate on how many civilians have been injured during coalition airstrikes and fighting between U.S. and Iraqi troops, Simpson said. The agency said in a statement that hundreds of civilians were being injured daily.
The ICRC said it stopped counting as the numbers grew and its delegates were unable to reach all medical facilities.
"Nobody is adding up all the numbers, but it's clear they are huge," Simpson said.
The International Committee of the Red Cross reported one dead and 114 wounded in Baghdad in the first two days of the war and said 280 were injured April 1 in what Iraqis claimed was a U.S. helicopter strike on a residential neighborhood in Hillah, south of Baghdad.
"The hospitals have reached their limit," said ICRC spokeswoman Nada Doumani told reporters Tuesday. "Staff are working around the clock" and face a shortage of anesthetics.
ICRC staff who delivered supplies to the 650-bed Medical City complex in Baghdad on Tuesday found that there was neither water nor power and only six out of 27 operating rooms could be used, the agency said.
Engineers are trying to restore the water supply to the hospital and to the city, the ICRC said.
"The water supply for Baghdad is becoming an issue of major concern following reports that the Qanat raw water pumping station in the north of the city has stopped functioning," the agency said. Without electricity from the regular grid, hospitals and pumping stations would have to use generators to function.
U.S. Central Command has said repeatedly that it does not target Iraqi civilians and is pinpointing that sites U.S. forces strike to avoid unintended deaths or injuries.
In a strike on "leadership targets" overnight Monday, U.S. bombs hit a residential neighborhood where Saddam and or his sons and other regime commanders were thought to be staying. Iraqi rescue workers pulled three bodies from the rubble — an elderly man, a young woman and a little boy — but said the toll could be as high as 14.
Central Command or CENTCOM has launched investigations into several incidents of alleged civilian casualties resulting from American attacks on Iraq.
Some of the incidents have been alleged by the Iraqi government, which has obvious motives for making false claims.
CENTCOM has already investigated and refuted claims that a U.S. missile killed 14 people in a Baghdad market on March 26.
Other incidents being probed include other attacks on Baghdad markets killing over 60 people, alleged cluster bombing in Hillah, attacks on two buses, a shooting at a checkpoint that killed seven civilians and the killing of three journalists in Baghdad Tuesday.
An Al-Jazeera journalist was killed when U.S. troops were fired upon and returned fire. Elsewhere in Baghdad, two cameramen were killed when a U.S. tank fired on the Palestine Hotel, where many reporters are staying. U.S. military spokesmen said shots had been fired from the hotel, but witnesses denied this.
Abu Dhabi TV said its office had also been hit.
CENTCOM said it was not targeting the media.
Even when civilian deaths are the direct result of a U.S. combat operation, CENTCOM and the Pentagon have insisted throughout the campaign that any noncombatant casualties were Iraq's fault.
They place the blame on Iraqi military's tactics — like using human shields, irregular forces out of uniform, and at least one suicide bomber — and its strategy of locating military facilities near civilian areas.
In related news, Japan will contribute up to $100 million in emergency humanitarian aid for people affected by the war in Iraq, the foreign minister announced Wednesday.